The Southern California WIHS Consortium (SCWC) has been established to participate in the national WIHS/HERS Project, in order to define (1) the spectrum and course of HIV infection in women; (2) the pattern and rate of decline of CD4 cells in these women; (3) those factors which may delay or accelerate immune dysfunction; and (4) those factors which influence the quantity and quality of survival. Further aims include the determination of (1) the rate of incident HIV seroconversion and factors associated with infection in a cohort of HIV-negative women at risk; and (2) the feasibility of vaccine trials in this group. To these ends, our SCWC Consortium was designed to accrue subjects who will represent the rich ethnic, cultural, and socioeconomic diversity which characterizes Southern California. A total of 600 HIV-positive patients, and 150 HIV-negative women at risk will be accrued from seven sites: (1) University of Southern California School of Medicine and the Los Angeles County-USC Medical Center; (2) The Charles Drew University of Medicine, and the Martin Luther King Medical Center; (3) The AIDS Healthcare Foundation, and Southwest Community Based AIDS Treatment Group (AmFAR CBCT Network); (4) SEARCH Alliance (AmFAR CBCT Network); (5) the Santa Barbara County Department of Health Services; (6) T.H.E. Clinic for Women, a private non-profit community clinic providing comprehensive health care to minority women; and (7) Prototypes/W.A.R.N. + Women's Center, a center for the care and counseling of women with drug use history. Through this Consortium, of the 600 HIV-positives, 42% will be Latina; 31% African-American; 25% Caucasian; and 2% other. Sources of HIV infection will include approximately 60% by heterosexual contact; 18% by injection drug use; 9% by transfusion; and 13% by unknown factors. Our identified pool of 150 HIV negative women at risk provides an almost identical distribution of ethnic and risk-behavior groups. On-going participation from a Community Advisory Board (CAB), along with strong, existing linkages with multiple AIDS service agencies will allow accrual of the planned cohort. Bilingual personnel, sensitive to cultural issues will be hired; 70% of the PI/Co-PIs on this grant are women or minorities SCWC personnel from all sites will undergo specific Training Sessions. By provision of specific comprehensive support services, including transportation; child care; food; social services and other incentives; and a patient tracking system, we will retain approximately 80% of the accrued cohort. HERS study procedures will be refined and used in accordance with central WIHS guidelines to follow all subjects over time.